Gram Negative Bacteria selective for isolation Macconkey Enterobacteriaceae Gram 0 Agar differential is lactose non lactose fermentas fermentas
Gram Negative Bacteria
selective forisolation Macconkey Enterobacteriaceae Gram0
Agar differentialis
lactose non lactosefermentas fermentas
(E.coli)1. Escherichia coli
Mostcommon typelactose tNo specific character DrycolonyRods
2. Klebsiella
• Large mucoid polysaccharide capsule .
weakor lateqlactose fermentas
Give Mucoid colonybecause it is encapsulated
3. EnterobacterNo specificcharacterSimilar to Ecoli
4. Citrobacter
o Gram negative rods , nonlactose fermenter
o Swarming motility ( flagellated )
o Prevent swarming by culturingit on CLED or Macconkey media
Proteus
e
pedal
spread inthe Media
used More 4than Macc
I l I d
identified by :•Gram negative rods•odor : grape-like smell.•Oxidase positive.•Produce different pigments colors:
• Pyocyanine (blue-green)• Pyoverdin (fluorescent yellow –greenish
pigment).• Pyorubrin (red).• Pyomelanin (brown).
Pseudomonas aeruginosaMost isolated qspecie
non lactosefermentas
r Veryspecialcharacter
Gives violet color
IThe color depend on the type ofPigment produced
Pseudomonas aeruginosa on mueller hintion agar
gm 1 Pr
TheTediatakesthecolor of the pigment